


Cross My Soul

by smashedkittkate



Category: Soriel - Fandom, Underfell - Fandom, Undertale (Video Game)
Genre: Angst, F/M, Fluff and Angst, M/M, Multi, Relationship(s), Soriel, Strong Language, Tsundere Flowey, Tsundere Sans
Language: English
Status: In-Progress
Published: 2017-03-26
Updated: 2017-03-25
Packaged: 2018-10-10 18:17:52
Rating: Teen And Up Audiences
Warnings: Graphic Depictions Of Violence
Chapters: 1
Words: 4,039
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/10444140
Author URL: https://archiveofourown.org/users/smashedkittkate/pseuds/smashedkittkate
Summary: UnderfellA promise is made and life gets a lot more difficult for sans. Dealing with life underground, a wondering human child and realizing his feeling for toriel would be more than enough for one monster to deal with.Monsters start disappearing and it seems ghost of the past are coming back.





	

**Author's Note:**

> First fan fic so please be don't be too hard on me.

It was an unusually windy night for then Snowdin forest, as Sans angrily stomped through the snow muttering to himself under his breath. You could barley hear what he was saying, the wind and loud sound of the dry snow crunching under his sneakers, but the longer he walked the louder he became. He was going on about the fight he had with his brother earlier, what caused him to be out in this damn cold wind anyways. It wasn’t that the brothers didn’t get along, they actually really did. But personalities collide and they where very different.

“How the fuck was it my fault that stupid dog snuck in and ate all the pasta?! At least something actually likes that shit.” Sans said to himself. “but no, it’s my fault for ‘NOT CONCELLING THE FORTRESS DOWN PROPERLY.’ It’s called a door lock bro, and what’s that got to do with this? Dogs don’t have fuckin thumbs.” He angrily bickers to himself as he walks.

Papyrus insisted that he go out and find the annoying dog that seems to plague the entire underground, no one knows the dogs’ owner or where it came from. It just always caused trouble and seemingly ridiculous episodes for monsters. Usually sans would have argued about going to chase the dog but today felt like if he heard anymore of papyrus yelling his skull would explode. So off he went.

Multiple short cuts latter and no annoying dog in sight, the thing he could seen now was the giant purple door. He hung around that ancient door many time, slacking off of work and telling knock knock jokes to what he thought was to himself. No one really went to that sight in the deepest part of the forest, everyone was more enthralled with Hotland and The Capital. Anyone who knew of the door knew it was locked with a strong barrier, magic from a monster strong enough to dust you instantly. Don’t you know? Small towns have the biggest secrets.

The wind seemed to have calmed down a bit by now and sans decided to sit down against the door. A lot of his energy was spent using his short cuts and chasing the mutt, ‘he deserves a rest now right?’ He thought to himself. No one really comes out this far so its real quiet, no bro to wake you up with him and his friend screaming downstairs. The trees around the door created a wind block and somehow the door seemed a bit warm. It was honestly one of the most comfortable place in the underground for him. The thought of going home now wasn’t a very pleasant one, probably would get yelled at for not finding the little mutt. He’d had enough contention for the day and now he could drop the cocky grin he wore most of the time. He could be himself and feel like tired trash.

He sat there for an unknown amount of time listening to the sound of silence that would only be cut through but wind and the rustle of the swaying trees. He then suddenly remembered the knock knock joke he made up today. He took up gigs at club MTT when he needed the extra gold. Jokes where sans means of escaping his emotions, no one knows your hidden depression if your always joking right? It made a great mask. Sometimes it was almost a high. Moving his arm back to the door behind him he knocked his knuckles twice and said “knock knock.” 

*shuffle*

He heard a shuffle. Or wait, did he hear a shuffle? Was it the wind? No one come out here, sans thought to himself. He heard only silence now so he decided it was the wind and on he went with his joke. “who’s there?” He said. “Dumbbell. Dumbbell who? Dumbbells not working that why I knocked. Heheh” He chuckled to himself. Oh how sans loves word play. He then continues his jokes.

“knock knock.  
Who’s there?  
Urine.  
Urine who?  
Urine secure don’t know what for.   
Heh”

“knock knock.  
Who’s there?   
Waiter.  
Waiter who?   
Waiter till I get my hands on you”

As he knocked again and said ‘knock knock’ He was shocked to hear what came next. “Who is there?” a stern and strong female voice answered. The demand in her voice made him jump and pause a while before answering her through the door.

“Uhhh” He could feel his forehead start to bead with sweat. “dishes” He spat.

“Dishes who?” she said. Jeez she sounds suspicious of me. Sans thought.

“Dishes a bad joke.”

“Ha” a cough of a laugh came from her. There was a pause and then a “haha… Hahahahahaha!” an odd joyfully fit of laughter came out. It almost sounded like someone who hadn’t laughed in years.   
Man what a beautiful sound it was. Sans could hardly believe that came from a monster down there. It was a musical melody to his ear canals and her voice carried a beautiful tone to match.

“heheheh” well this is new. He thought, feeling slightly light headed, a bit of anxiety fading with the sound of her laughter. I might have been because he’d been caught telling jokes with his guard down, that cocky mask of his gone. Or because of how happy that laughter sounded. No one ever laughter that hard over a knock knock joke besides him.

He told a few more jokes, maybe about a dozen, out of curiosity, getting a pretty great response each time. But even with all the Laughs that awkward feeling inside grew.

“Uhhhh….” Yep. He was caught telling lame jokes. He was happy the person was behind the door cause, well, at least they couldn’t see him. A rare blush of embarrassment creeper across his face.  
Welp time to go. Time to get the fuck outta here. Sans thought as he started to stand up. Right as he was about to use a short cut he heard a knock.

“knock knock.” She said

Wait. What. “Ehh w-who’s there?”

“Old lady.”

“Old lady who?”

There was a brief silence after that. She really forget the punchline?? Psh, amateur.

“OHHH, I don’t know you could yodel!” she responded.

Nevermind ameture.

He burst into laughter “Hehehehehehehe, shit heheheh man lady that was bad.” He said in between laughs.

“And yours was any better?” the lady said a little defensive.

“heh, no way mine was probably worse but that’s what makes them so damn funny.” Sans responded.

“Hmmm, I suppose you’re right.” Her tone lightened.

“Uhmm, sorry to bother ya. Didn’t know anyone lived in this dump.”

“Well technically this isn’t part of my home, so I won’t take too much offence from that comment” she answered in a warning tone.

“whoa wait, no. No we call this part of the forest the ‘Ruin door’. Just though of it as a sealed up ghost town. Heh, it’s fitting right? Sense only ghosts can go in there? Heh.” Okay that was a cheep way to cover yer ass sans. He thought.

“Phfffftt, yeah I can’t keep those pesky little apparitions out.” She said with a laugh.

“Heheh knock knock”

“Who is there?”

“ice cream”

“Ice cream, who?”

“Ice cream every time I see a ghost.”

“hahahaha! My, that one sure did rattle my chains.” She responded with giggles.

“heh jeez, it’s not very lady like to be so transparent.”

“Well I su-spector-ed you wouldn’t care.” 

“Ha, yeah that’s pretty paranormal nowadays.” 

“Isn’t it supernatural how things are?” 

“Hahahahahaha man lady” He laughed. No one joked around with him like this, it almost felt like a dream and like any other dream he could feel himself waking up. “Oh.-oh shit.” Papyrus. He’d been out way too long, he could feel it was very late at night now. He’s probably pretty mad. You may not see it with that hard, tough exterior of his But Papyrus gets pretty worried when sans stays out too late.

“Fuck, it’s late. He’s gonna fuckin kill me.” Sans said standing up.

“What? Who?” the woman be hind the door answered confused and a little startled.

“oh uh he probably won’t kill me. My brother. I gotta get back to him heh he worries if I'm not home at night. He’ll probably start to hunt me down soon.”

“You should probably get out of this area then.” She said a little bitter sweet.

“Uhhh yeah…. Well thanks for the Laughs. It was fun.” Sans started to walk away, but then-

“W-wait!” she stuttered. Sans stopped and turned towards the sound. “ I um. If you feel like it I’d um. I’d be Willing with entertaining you again if you insist. I mean.” She then sighed and paused to compose her thoughts. “I guess what I’m trying to say is.” Another pause. “Please, feel free to come back. Tomorrow?”

This shocked sans. She actually wants to talk with him again? He felt an odd warm fuzzy feeling. 

“pshhh jeez lady, don’t you have anything better to do? Hehehe” Come on. He just had to ruin it.

“Fine. Don’t ever come back then.” She said.

“hahahaha na, I’ll come back.”

“tomorrow?”

“tomorrow.”

With that he walked off, back home with a small smile.

 

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

 

It was dark. Wonderfully black and comfortable with silence. Something starts to disturb this blissful comfort though, it sounds like static. As the darkness started to fade with the light coming in the noise became more, talking? Nope. Yelling. “SANS. SANS! WAKE UP NOW!!” It was papyrus. It was a dream again. As sans slowly started to open his eyes he notice the he was in a sort of sitting position on his matters. Papyrus was kneeling on the floor roughly trying to put sans jacket on his sleepy limp bones.

“Few more years, dude.” He grumbled annoyed, pushing papyrus away with a foot while trying to lay back down.

“NO YOU DON’T YOU LAZY LUMP OF BONES.” He says to sans as he aggressively zipped up his jacket, accidentally knocking him in the head. “WE HAVE WORK TO GO TO AND YOU WON’T MAKE ME LOOK BAD BY SLOUCHING OFF.”

“heh my baby bones bro still needs me with him. Awww. Hehehe.” Teasing his brother in private was one of his favorite things, family bickering. Arguing always made him slightly happy. He sure as hell couldn’t do it in public, it would ruin papyrus’ image that he worked so hard on. And sans knew it would secretly hurt his feelings.

“OH SHUT UP! NOW GET UP AND GO!” He said with a stomp. 

“nope.”

“WHAT?”

“did I fuckin stutter?” Sans said half giggling.

“YOU HAVE THREE SECONDS TO GET UP.” 1. 2. 3. “FINE THEN.”

There was about a minute of silence. 

Huh, the actually left me. Maybe now I can go back to sleep. Sans thought as he started to curl up into a ball.

Just then sans felt a tug, he was being pulled out of his bed by his hood.

“NYEH HEH LETS GO.”

“alright, alright. Whatever bro.”

“IT’S BOSS AT WORK NOW. REMEMBER.”

“OK, bossbro.”

“SANSSSSS.” Papyrus yelled frustrated.

Papyrus ended up dragging him all the way to his post. In all honesty sans didn’t mind it, it was easier than walking and the snow made it a smooth ride, he fell asleep part of the way. The only bad part was going down the stairs. Stair steps and bones don’t go very good together.

The brothers have had jobs as sentries for a while now but now their boss and papyrus’ best friend, undyne head of the royal guard, finally decided to give him a promotion from plain old sentry to being the head of the Snowdin section of royal guard. He’s pretty much just her glorified second hand man, don’t let if fool you though he’s a real strong monster. Sans on the other hand didn’t ever care for high status jobs, if it payed decent and allowed him to slack off now and then it was good enough for him. Now he didn’t have to work himself to the bone to pay for his baby brother he deserved a break. He could never let go off the hot dog stands though, it was just his thing.

Honestly it was quite long walk to sans post, it was right on the edge of the forest right by his favorite door. Papyrus’ station was before sans and he never ventured farther than sans station. Only going over there to check up on him. “ALRIGHT GET TO WORK AND NO SLEEPING ON THE JOB.” Papyrus said as he let go of sans hood adjusting the smaller skeleton onto the seat behind the post.

“kay bro.” 

“IT’S BOSS!! GET IT RIGHT! DON’T YOU DARE FALL ASLEEP. YOU’RE SUPPOSED TO STAY VIGILANT AND WATCH FOR ANY HUMAN THAT MAY CROSS THE AREA. I’M OFF TO CHECK UP ON THE OTHER SENTRIES AND WHEN I GET BACK YOU BETTER NOT-“

“alright already! Get going boss.” He snapped back.

“NYEHH.” Papyrus smirked as he began to walk off. The sound of his crunchy foot steps in the snow eventually faded. Damn the more he hang around that fish woman the more he gets to be an ass. Sans though.

Sans didn’t take his job serious most of the time, papyrus didn’t bend on the rules though, so here he was half awake in the morning in one of the deepest parts of the forest. What’s the point? He thought. The last time a human fell into the underground was years ago, back when he was young. The king accumulated six human souls, supposedly one away from breaking the barrier. It’s not like another is going to pop up right? That would be too lucky.

The monsters in the underground sure did hold a grudge against humanity, first they betrayed monster kind and then they murdered the royal family’s children. The king went into a rage and declared war on humans once again, no human was allowed to live in the underground and the king would use the souls to destroy the barrier. And his wife? No one knows what happened to her. Maybe she died. 

Sans slept most of the time on his job that day, taking short cuts every now and then to sell a hot cat to random hangery monsters. An uneventful day. He could feel his eye sockets start to close for another nap but right before he could drift off he heard the tell tale signs of footsteps in the crunchy snow. 

Now one thing to know about spending most of your life in a snowy place is you learn to recognizing how each monsters foot steps sound different. He knew this wasn’t papyrus, he makes light stomping sounds in the snow, nor was it a regular coming to get a hot dog or cat. These foot steps sounded like long flat feet.

Oh great. He thought. He suddenly remembered who they belonged to.

“Alright, wake up you little shit.” 

Sans eye sockets snapped open to the sight of a blue rabbit monster, Guy. Guy was the local scream-cream vendor, he usually never had any trouble with before but that expression he was making told sans he wasn’t here to borrow a cup of ketchup from a neighbor.

“what’s got your tail in a bunch, blue bell?” Sans shot back. Hey, he started it.

“Cut the crap.” The bunny spat back. “don’t get all proud. Quit going into my vending area, those are my regulars you keep stealing.”

“Ha so what?” He answered. “It’s not my fault my food tastes better.”

“Better!? Your mysteries in a bun are making monsters around here sick! I haven’t seen certain customers in weeks!!” Guy’s completion was turning blue to red (purple?) at this point.

“And you think that’s my fault?? Your cold food in this cold weather is probably what’s making them sick.” A shit eating grin appeared on sans face. “You know what they say, fluff butt, two colds don’t make a hot.” Or was it two rights make a hot? I don’t know, that’s how I usually get to hotland. 

“why you little-“ 

Guy jumped forward and swung his fist down at sans but it just went though the empty space where the skeleton should have been. The force of his motion made him stumble around in a clumsy 180° turn. He saw sans for a split second in front of him before he felt an impact to his abdomin. Guy crumbles to the ground holding his stomach, trying to catch his breath. He looked back up expecting to see sans standing over him but yet again there was a blank space in from the of him.

“You okay there bud?” his voice called behind guy. “You just suddenly feel, you’d better be careful. Don’t want anything worse to happen to you, right?”

Once guy was steady on his feet he turned around. He could clearly see sans in the same spot he was before at his stand/post but one thing was different. The lights in his eyes where gone, completely void of light. He didn’t quite understand what just happened but he got the hint.

“Little freak” Guy turned to leave. “don’t think this is the end.”  
Sans felt relief as he watched guy walk away but he also felt something else. A shiver went down his spine but it wasn’t from the cold air around him. Something was going on and he didn’t have a good feeling about it.

 

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

 

The rest of his shift was surprisingly uneventful. A few more customers, and surprisingly no papyrus. He figured the first day of the new job must be busy for him. So right as his shift ended he began to walk to the giant door.

With a light thump and a short slide down he sat in his usual spot. “Knock knock” He said while knocking the door behind him.

“Who is there?”

“Theodore.”

“Theodore who?”

“theodoors locked, come on its cold out here Heheh” Sans chuckled to himself a little hopeful.

“Oh, are you feeling ice-solated?” she replied without a beat.

He knew it probably wouldn’t work but it’s always worth a try to get her out.

“Nah, you just int-ice me lady.” 

“hahaha, oh my, oh Brilliant.” She answered.

“So how’s life on the other side?

“Dreary as always. How is it for you? How that brother of yours?”

“Shit. Bossy as ever, but hey, that’s a good sign. Means he’s happy when he pushes me around.” He slightly scoffed at the end.

“I assume he got the promotion then?”

“Hah, how’d ya guess lady?”

“Intuition. And the way you said it. Why must you allow him to push him you around so much? You’re eldest and have been taking care of him for years.” She asked. She had heard a lot of stories of the two brothers.

“It’s his way of showing he cares, family trait I guess” Sans spoke back softly.

“hmmm… family…” she said in a melancholy tone.

“Uhhh sorry. Didn’t mean to strike a cord. I know you don’t like talking about family or kids for some reason…” she would either get mad or sad when the subject was brought up. Sans didn’t question her too much about, everyone has there secrets. He did find out she had kids and a husband. HAD being the key word. He figured something real messed up must of happened for her to be alone, never leaving the other side of the door. “So, uh you alright? That’s not a tone I usually hear from ya.”

“Yes, I am fine.” She said in a stiff tone.

“Bull shit. Come on, tell me the truth.” She couldn’t fool him.

“Sigh…” There was a long pause. So long it almost seemed as though she vanished. “I encountered a few things today. It made me remember things I don’t want to think about. Even so, I can’t bring myself to get rid of it.”

“Was it the infamous annoying dog? I don’t know how the hell it gets around so fast.” Especially without having my short cuts. Sans thought to himself.

“No, well yes, I have seen the dog around more often than usual. But that’s not what I meant. It’s a human-“

What???

“A human child. I wish to keep and protect them, no matter the cost.” She said in a stern tone.

“whoa, whoa, lady you can’t be serious. A human hasn’t fallen down here in decades and you want to keep it like a pet? Don’t you know how much trouble you would be in if someone where to find out you’d been hiding it?”

“I do not care. I don’t care about the kings orders, the king is a fool.”

“Shit.. you can’t say that kind of stuff out loud. Oh my God…” He said a bit shocked and admittedly impressed. No one would say that out loud, not in fear or the king. No, they didn’t want to evoke the Rath of the Captain of the royal guard, Undyne.

“This is something I deeply care about, something I believe in. After my children died I swore to protect all the youth around me, no matter what species they where.”

“Well… I guess I understand that…” Sans mind wandered to papyrus and him. Sans was so young when he had to take over the care of his younger brother. Even now with all the fights they have he wouldn’t take back what happened all those years ago. He’ll protect his little brother always. “okay… but what if, I dunno, it wants to leave? You gonna keep it on a leash?” This situation was still a bit unbelievable for him.

“A child is not a dog, my friend.” She said in a warning tone.

“HA right.” That made him laugh. “I’ve never seen a dog around here with a leash on. Only bunnies. Haha They must have some weird kinks.”

“Oh….Oh dear…” she said. “hahaha oh dear.”

They laughed together for a bit, slowly dieing down into a comfortable silence.

“Ahhh…” she then sighed. “My friend, I have a favor to ask of you. I told you this because I know I may not be able to keep them.” She paused. “If a human where to ever come though this door, please could you… could you not…?” 

She sounded like she was having trouble getting the words out and the it all faded into silence. Snow started to Fall around sans, somehow making the atmosphere more silent.

Don’t do what? Kill them? Take their soul? It’s all pointless. I gave up on that dream a long time ago. It all feels so redundant anyway. 

“sigh… don’t worry lady. I’ll keep a eye out for them.” She won’t get it. “I won’t hurt a hair on their head. I promise...” I promise? 

Sans was shocked by his last words. They just sort of slipped out of his mouth.

“You’ll watch over them?” the lady said in a surprised tone.

“Yeah. I mean what the hell? It could be interesting and besides, you mean a lot to me…” 

“I can’t…. thank you enough. My dear friend….you will promise?  
Sans sighed. What the hell am I getting myself into? I never promise to anyone. But this lady… I don’t even know her name and I’m hooked on her.

All the memories from their past deep conversations, cold nights, and confessions he had only ever told to her all flooded his mind. Something about being separated by the door, never seeing each other’s judging face made him open up. He never did that before. Always keep a safe distance he told himself. But before he even knew it he was enthralled.

“ah man, lady, why do you do this?” He said softly to himself while looking at his snow covered sneekers.

“What was that? I could quit hear it.”

“nothing….” He rested his skull on the door while he looked up at the cave ceiling, making a small klunk sound. He slowly closed his eyes sockets, hoping he wouldn’t regret this choice. “Yeah, I promise. Hehe, cross my soul and hope to dust.”


End file.
